Oil and gas well separation apparatus

ABSTRACT

An oil and water separation apparatus includes a pair of spaced apart vessels, the first vessel having an interior for holding liquid and a separator unit that is positioned in the interior of the first vessel. The separator unit receives incoming flow at its upper end portion. This flow fills the interior of the separator. The inclined walls of the separator help accumulate oil that moves upwardly therewithin. Lowermost pipes discharge water from the separator. A plurality of vertically spaced apart conduits are positioned around the exterior wall of the separator and communicate with its interior. Each of the vertical openings has a larger cross sectional area base portion and a smaller cross sectional area top through which oil can exit. Accumulated oil can be channeled away from recycling. Water escaping the first vessel enters the second vessel where it encounters a plurality of alternating baffles and filters that further clarify any water that is discharged from the first vessel. Additional filtration units can be positioned down stream of the second vessel for removing any trace amounts of waste product that are affluent from the second vessel.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. Ser. No. 08/851,792, filedMay 6, 1997, now U.S. Pat. No. 5,922,064.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable

REFERENCE TO A "MICROFICHE APPENDIX"

Not applicable

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to the treatment of waste water, and moreparticularly, to the treatment of a waste water stream that includesoil, water and gas. More particularly, the present invention relates toan improved oil/water separating system that provides a vessel having aninterior that can be filled with liquid and a separator that is immersedin the liquid within the vessel, the separator having a conically shapedwall that funnels and accumulates oil as it moves upwardly and whereinnumerous vertical conduits arranged about the wall of the separatorchannel collected oil upwardly, each of the vertical conduits beingwider at the base than at the top.

2. General Background of the Invention

The treatment of waste water that contains oil is a complex problem thatis more complicated when very high volumes of waste water flow areinvolved.

BRIEF SUMMARY OF THE INVENTION

The present invention provides an improved oil and water separationsystem that can be used to treat high volumes of waste water wherein theseparator oil can be reclaimed for recycling.

The apparatus of the present invention includes a first vessel having aninterior for holding liquid, a flow inlet and a flow outlet.

A second vessel is spaced from the first vessel and has an interior forholding liquid, a flow inlet and a flow outlet. The flow inlet of thesecond vessel communicates with the flow outlet of the first vessel sothat effluent from the first vessel enters the second vessel.

A separating unit is immersed in the interior of the first vessel, beingsurrounded by fluid that is contained within the interior of the firstvessel.

The separated fluid receives oil containing waste water from theincoming flow line by communicating at its upper end with the incomingflow line.

The separator unit is preferably cone shaped, having a plurality ofinclined wall portions that have a plurality of openings. Openingsinclude vertically and circumferentially spaced vertical conduitopenings positioned on the inclined wall. The majority of the openingsare positioned below the upper inlet portion of the separator unit.

Oil and water can stratify within the interior of the first vessel andlikewise within the interior of the separator unit. The combination ofthe inclined walls of the separator unit and the gradually decreasingarea of the conduits functions to stratify oil contained within theinterior of the separator unit and to accumulate and thicken oil as itmoves upwardly in the separator unit toward recycling.

BRIEF DESCRIPTION OF THE DRAWINGS

For a further understanding of the nature, objects, and advantages ofthe present invention, reference should be had to the following detaileddescription, read in conjunction with the following drawings, whereinlike reference numerals denote like elements and wherein:

FIG. 1 is an elevational view of the preferred embodiment of theapparatus of the present invention;

FIG. 2 is a fragmentary elevational view of the preferred embodiment ofthe apparatus of the present invention illustrating the separator unitportion; and

FIG. 3 is a fragmentary elevational view of the preferred embodiment ofthe apparatus of the present invention illustrating a second separatorunit portion thereof.

DETAILED DESCRIPTION OF THE INVENTION

FIGS. 1-3 show the preferred embodiment of the apparatus of the presentinvention designated generally by the numeral 10. Oil-water-gasseparating apparatus includes a support frame 11 that can be transportedfrom one job location to another as desired. A main inlet flow line 12carries selected waste water stream to surge tank 13 and then to primaryvessel 14. A main mixture inlet 13 can communicate with the main inlet12 so that multiple streams of waste water can be conveyed to theprimary vessel 14.

The primary vessel 14 comprises a continuous outer wall 15 that definesan interior 16 for containing liquid. Cover 17 forms a seal over thevessel 14 and its interior 16 so that gas can be accumulated at theupper portion of the vessel 14 adjacent to cover 17.

During use, liquid is transmitted via main inlet 12 and secondary inlet13 to interior 16 and vessel 14. Within the vessel interior 16, multiplelevels of fluid are defined as the oil and the water stratify. In FIGS.1 and 2, an oil level is indicated as 18, that being the uppermost fluidlevel within interior 16. Oil that stratifies is concentrated at oillevel 18 for recycling.

The level 19 defines the upper level of a oil and water mixture that ispositioned immediately below the pure oil level 18.

Below the pure oil level 18 and the mixed oil/water level 19, arrow 20indicates the pure water level. Thus, the heaviest liquid within theinterior 16 of vessel 14 is water, and it assumes the lowest levelwithin interior 16 of vessel 14.

Baffle 21 extends transversely across vessels 14 interior to prevent theflow of oil to outlet 41. Baffle 21 has openings 22 that allow fluidflow as shown by arrows 23 through openings 22. Otherwise, fluid thatstrikes the baffle 21 travels upwardly in interior 16 to stratify intooil and water levels as aforedecribed.

Separating unit 24 has an upper end portion 25 and a lower end portion26. A plurality of water outlet pipes 27 are positioned at lower endportion 26 of separator unit 24. Separator unit 24 is in the form of aconically shaped wall 24A that has a plurality of vertical outletconduits 28-39 spaced over wall 24A as shown in FIG. 2. Each of theoutlet conduits 28-39 is generally trapezoidally shaped so that thebottom of each outlet conduit 28-39 is wider than the top. Thisfunctions to accumulate and gather oil droplets together as they moveupwardly during stratification.

Inlet 40 defines the connection between main inlet line 12 and separatorunit 24. Outlet 41 allows treated water to exit vessel 14 and enter asecond vessel 43 via outlet flow line 42. Vessel 43 has an inlet 44 anda continuous outer sidewall 43A and is generally cylindrically shaped.As with vessel 14, vessel 43 has a cover 45 and an interior 46 forcontaining liquid. A series of parallel, vertically oriented baffles47-51 create a circuitous path for water that travels through theinterior 46 as shown in FIG. 1. A plurality of transversely extending,generally horizontal filters 52, 56 are positioned to span betweenadjacent baffles and/or between a baffle and the side wall 43A of vessel43 as shown in FIG. 1. Outlet pipe 57 empties water from interior 46 ofvessel 43 after it has been treated with baffles 47-51 and filters52-56.

Level control valve 58 can be used to control the level of fluid withinthe interior 46 of vessel 43. Final filtration units 59, 60 can be usedto further clarify liquid that exits vessel 43 via outlet pipe 47. Thefinal discharge line 61 provides treated water that leaves filter units59, 60. As an optional feature, makeup water line 62 can be used to addwater to the interior 16 of vessel 14 as shown by arrow 63 in FIG. 1.

A second separator 64 can optionally be provided to the interior 16 ofvessel 14. Separator 64 extends transversely across interior 16 ofvessel 14. Separator 64 is of an inverse V-shape in cross section andcan provide a baffle 65 to discourage the flow of oil to outlet 41. Anoil collection pipe 66 can be positioned within separator 64 forwithdrawing any oil that accumulates at the upper end portion of theseparator 64.

The apparatus 10 of the present invention provides a plurality of ductsfor removing gas from the waste water stream that is transmitted to theapparatus 10. In that regard, gas conveying ducts 67, 69 and 70 areprovided, all of which accumulate gas for communication to outlet 74.The duct 71 is connected to vessel 44 at outlet 69. The duct 72 isconnected to vessel 14 at outlet 69. One or more blowers 73 can beutilized to properly ventilate each of the treatment vessels 14, 43 asshown in FIG. 1. Air jets 76 can be positioned at various locations asseen in FIG. 1. In FIG. 1, one or more oil probes 75 can be positionedto detect the presence of accumulated oil.

Parts List

The following is a list of suitable parts and materials for the variouselements of the preferred embodiment of the present invention.

Part Number Description

10 oil-water separating apparatus

11 support frame

12 main inlet flow line

13 surge tank

14 vessel

15 wall

16 interior

17 cover

18 oil level

19 mixed oil/water level

20 water level

21 baffle

22 openings

23 arrow

24 separator unit

24A conical wall

25 upper end portion

26 lower end portion

27 water outlet pipe

28 vertical outlet pipe

29 vertical outlet pipe

30 vertical outlet pipe

31 vertical outlet pipe

32 vertical outlet pipe

33 vertical outlet pipe

34 vertical outlet pipe

35 vertical outlet pipe

36 vertical outlet pipe

37 vertical outlet pipe

38 vertical outlet pipe

39 vertical outlet pipe

40 inlet

41 outlet

42 outlet flow line

43 vessel

43A cylindrical wall

44 inlet

45 cover

46 interior

47 baffle

48 baffle

49 baffle

50 baffle

51 baffle

52 filter

53 filter

54 filter

55 filter

56 filter

57 outlet pipe

58 level control valve

59 filter

60 filter

61 discharge

62 make up water line

63 arrow

64 separator cone

65 baffle

66 oil collection pipe

67 gas duct

68 arrow

69 outlet

70 outlet

71 duct

72 duct

73 blower

74 outlet

75 oil water probe

76 air jets

The foregoing embodiments are presented by way of example only; thescope of the present invention is to be limited only by the followingclaims.

What is claimed is:
 1. An oily wastewater treatment apparatuscomprising:a) an incoming flowline for carrying an oil containing wastewater stream to be treated; b) a treatment vessel having an interior forholding liquid, a flow inlet that communicates with the incomingflowline and a flow outlet; c) a separator unit positioned in theinterior of the vessel and surrounded by fluid contained within theinterior of the vessel; d) the separator unit being generally coneshaped, having an outer wall that is cone shaped, comprised of spacedapart inclined wall portions that have a plurality of openings spacedvertically and circumferentially about the inclined walls; e) theseparator unit having an upper inlet that receives waste water from theincoming flowline; f) the majority of the openings being positionedbelow the upper inlet of the separator unit; g) wherein oil and watercan stratify within the interior of the vessel; h) an oil discharge linefor removing oil from the interior of the vessel that has separated bystratifying from other fluid contained within the vessel.
 2. Theapparatus of claim 1 further comprising a second vessel in communicationwith the first vessel, the second treatment vessel being positioned toreceive fluid below the oil that has separated by stratifying, thesecond treatment vessel having a flow inlet and a flow outlet.
 3. Theapparatus of claim 2 further comprising a gas collection flowline forremoving gas that rises to the top of either vessel.
 4. The apparatus ofclaim 2 further comprising a gas flowline extending from the top of thesecond treatment vessel for transmitting gas that accumulates in thesecond treatment unit to the top of the first vessel.
 5. The apparatusof claim 1 wherein the first treatment vessel has openings positioned atthree separate elevational positions.
 6. The apparatus of claim 1wherein oil contained within the interior of the first treatment vesselengages and travels along an interior surface of the outer wall of thetreatment vessel until said oil reaches an opening.
 7. The apparatus ofclaim 1 wherein the vessel has a lower end portion with a fluid outletfor discharging fluid that is heavier than oil into the interior of thevessel.
 8. The apparatus of claim 1 wherein each of the openings has alower end portion and an upper end portion, the lower end portion beinglarger than the upper end portion.
 9. The apparatus of claim 8 whereinthe openings comprise conduits that extend vertically from the wallportions of the vessel.
 10. A oil and water separation apparatuscomprising:a) an incoming flowline for conveying an oil containing wastewater stream to be treated; b) a vessel having an outer wall, aninterior for holding liquid, a flow inlet and a flow outlet; c) aseparator unit positioned in the interior of the vessel, the separatorunit receiving oil containing waste water fluid from the incomingflowline; e) the separator unit being cone shaped, having an outerinclined walls, an upper end portion, a lower end portion, a fluidcontaining interior and being tapered between upper and lower endportions, the upper end portion being smaller and the lower end portionbeing larger; f) a plurality of openings in the inclined walls of theseparator unit including openings that are spaced vertically andcircumferentially about the inclined walls; g) the separator unit havingan upper inlet that receives waste water from the incoming flowline; h)the majority of the openings being positioned below the upper inlet ofthe separator unit; i) wherein oil and water can stratify within theinterior of the vessel; and j) an oil discharge line for removing oilfrom the interior of the vessel that has separated by stratifying fromother fluid contained within the first vessel.
 11. A oil and waterseparation apparatus comprising:a) a vessel having an outer wall, aninterior for holding liquid, a flow inlet and a flow outlet; b) aseparator unit positioned in the interior of the first vessel andsurrounded by fluid contained within the interior of the first vessel,the separator unit receiving oil containing waste water fluid from theincoming flowline, so that the waste water stream preliminarily entersthe interior of the separator unit; c) the separator unit being coneshaped and having an outer inclined wall, an upper end portion, a lowerend portion, a fluid containing interior and being tapered between upperand lower end portions, the upper end portion being smaller and thelower end portion being larger; d) a plurality of openings in theinclined wall of the separator unit including openings that are spacedvertically and circumferentially about the inclined wall; e) theseparator unit having an upper inlet that receives waste water from theincoming flowline; f) the majority of the openings being positionedbelow the upper inlet of the separator unit; g) wherein oil and watercan stratify within the interior of the first vessel; and h) an oildischarge line for removing oil from the interior of the first vesselthat has separated by stratifying from other fluid contained within thefirst vessel.
 12. The apparatus of claim 10 further comprising a secondvessel in communication with the first vessel, the second treatmentvessel being positioned to receive fluid below the oil that hasseparated by stratifying, the second treatment vessel having a flowinlet and a flow outlet.
 13. The apparatus of claim 10 furthercomprising a gas collection flowline for removing gas that rises to thetop of either vessel.
 14. The apparatus of claim 10 further comprising agas flowline extending from the top of the second treatment vessel fortransmitting gas that accumulates in the second treatment unit to thetop of the first vessel.
 15. The apparatus of claim 10 wherein the firsttreatment vessel has openings positioned at three separate elevationalpositions.
 16. The apparatus of claim 10 wherein oil contained withinthe interior of the first treatment vessel engages and travels along aninterior surface of the outer wall of the treatment vessel until saidoil reaches an opening.
 17. The apparatus of claim 10 wherein the vesselhas a lower end portion with a fluid outlet for discharging fluid thatis heavier than oil into the interior of the vessel.
 18. The apparatusof claim 10 wherein each of the openings has a lower end portion and anupper end portion, the lower end portion being larger than the upper endportion.
 19. The apparatus of claim 10 wherein the openings compriseconduits that extend vertically from the wall portions of the vessel.